abstract introduction: smoking is one of the sanitary problems in world today. increasing smoking of cigarette and other tobacco products has concerned health managers and community responsible. in recent decades, smoking has increased specially in developing countries and the smokers are adding every year. the objective of this study is determination of smoking prevalence and its distribution ...

In this study a polypropylene material with talcum reinforcement used for sewer pipes has been subjected to an annealing procedure at 80°C, roughly 60°C above the actual application temperature, in air for a time period of 18 months. As expected, examination of the material showed no significant decrease in mechanical or fracture mechanical properties due to the temperature exposure. However, s...

the use of solar collectors in combination with heat pipes is rapidly growing in recent years.heat pipes, as heat transfer components, have undeniable advantages in comparison with other alternatives. the most important advantage is their high rate of heat transfer at minor temperature differences. although there have been numerous studies on the heat analysis or first thermodynamic analysis of...

this paper is about experimental results for partial reduction of vortex at vertical pipe intakes. one of the easiest and practical ways of reducing vortex effect is to use anti-vortex plates or baffles. these plates can be used to avoid the vortex completely or partially. this paper will concentrate on the latter case. rectangular plates with different dimensions have been placed at different ...

This study of 130 subjects was performed to obtain more data about the smoking habits and levels of carboxyhemoglobin in various types of pipe and cigar smokers. These smokers may be divided by history into primary or secondary smokers and also into current inhalers and noninhalers. Prior studies of carboxyhemoglobin levels have yielded conflicting results, presumably due to differences in curr...

The steady behavior of a rarefied gas in a circular pipe with a saw-like temperature distribution increasing and decreasing periodically in the direction of the pipe axis is investigated numerically by means of the direct simulation Monte Carlo method. It is shown that a steady one-way flow is induced in the pipe without the help of a pressure gradient for a wide range of the Knudsen number whe...

Buried steel fuel pipelines are critical lifelines for the society and the economy but are very vulnerable to earthquake-induced ground failure. Traversing seismic areas inevitably results in several pipe-fault crossings. Fault rupture forces a buried pipeline to undergo deformations that could be substantial and heavily endanger its integrity. Due to the grave consequences of a potential pipe ...

This paper proposes an in pipe inspection robot with the wall-pressing force adjustment using DC motor. It is developed for long distance inspection in sea-water pipelines such as horizontal pipelines and slope pipelines with large variable diameters from 600mm to 800mm. Its mechanical design consists of two modules as driving module and control module. The driving module has three pantograph t...

A systematic experimental study was conducted using a pilot-scale drinking water distribution system simulator to quantify the effect of hydrodynamics, total organic carbon (TOC), initial disinfectant levels, and pipe materials on chlorine decay and disinfection byproduct (DBP) formation. The first phase of the experiments focused on the variables of flow rate and pipe materials and their effec...

Construction of Industrial facilities involves a substantial amount of piping. Pipe spools are usually pre-fabricated from a number of raw pipes and pipe fittings (e.g. elbows, flanges, tees, etc.) in fabrication shops. Pipe spool fabrication is often affected by various disruptions from within or outside the shops. Previous research mainly focuses on shop layouts, dispatching rules, buffer loc...